An analysis and modeling method of the diagnostic characteristics of a mechanical or electromechanical system is presented. Diagnosability analysis is especially relevant given the complexities and functional interdependencies of modern-day systems, since improvements in diagnosability can lead to a reduction of a system's life-cycle costs. The diagnosis process of a...
The effects of the orifice geometry and the surface boundary condition on the heat transfer distribution to a flat surface of an impinging jet array were investigated. The jet array impinged normally onto the surface which was either isothermal or had a uniform heat flux. The experiments were performed for...
Eighteen Ponderosa Pine (Pinus ponderosa Dougl.ex.laws) veneer flitches
were randomly selected and crosscut into paired flitches. Serpentine-end-matched
(SEM) joints were machined in the flitches, joint amplitude equal to the width in
one half of the paired flitch and joint amplitude equal to 2/3 width in the other half
of the...
Lake Kinneret is Israel's only fresh water lake (unless you count the Dead Sea). It spans roughly 20km from north to south, and about 12km at its widest east west extent. It is not quite 50m deep at its deepest point. In late spring, the lake stratifies significantly and remains...
The implementation of concurrent engineering into many large
companies has greatly improved their product development processes.
These companies have seen significant gains in quality and customer
satisfaction with reduced product costs, defects, and time-to-market
(Lake, 1992). Many large companies have successfully employed this
relatively new product development philosophy. However, smaller...
The problem of simple mathematical models of laminar natural convective
flow within a long vertical parallel-plate channels and circular tubes kept at
uniformly heated walls is revisited to seek a clear physical understanding of heat
transfer mechanisms. A series solution method to analyze the fully developed flow
and an integral...
The present study proposes to investigate the flow structure of different arrays of jets impinging on a flat surface enclosed by three walls, creating a channel that forces the air to leave in one preferential direction, generating a self sustain crossflow. Details of both the mean and some turbulence quantities...
The metallurgy and superconductivity of the Nb-Ti-Ta ternary alloy system were studied. The Nb-Ti, and Ta-Ti binary samples, and Nb-Ti-Ta ternary samples were precipitation heat treated under different schedules. After the precipitating heat treatment, the samples were characterized by X-Ray Diffraction (XRD) techniques. Equilibrium binary and ternary phase diagrams based...
A model has been developed for accurate emulation of the complex behavior of high performance dynamometers used in a broad range of applications including manufacturing systems, biomechanics research, and crash testing. The key objective of this research has been to reach the proper balance between the accuracy of emulation and...
The characteristics of the free surface in an orifice driven by a periodic forcing function have been studied both theoretically and experimentally. In the theoretical study, two wall boundary condition cases were examined: 1) the radial velocity at the wall of the orifice is zero; and 2) the axial velocity...
Uncontrolled direct fire rockets exhibit high impact point dispersion, even at relatively short range, and as such have been employed as area weapons on the battlefield. In order to reduce the dispersion of a direct fire rocket, feedback control is employed to fire short-duration solid rocket pulses mounted near the...
Air compressors are a significant industrial energy user and therefore a prime target for industrial energy audits. The project goals were to develop a software tool, AIRMaster, develop a methodology for performing compressed air system audits, and conduct field audits to refine the methodology and assess savings potential from six...
The effectiveness of a direct fire penetrator projectile equipped with an actively controlled ram air mechanism is investigated through dynamic simulation. The ram air control mechanism consists of a rotary sleeve valve which directs air flow from an inlet at the center of the nose to side ports. The projectile...
Analyzing systems during the conceptual stages of design for characteristics essential to the ease of fault diagnosis is important in today's mechanical systems because consumers and manufacturers are becoming increasingly concerned with cost incurred over the life cycle of the system. The increase in complexity of modem mechanical systems can...
The effects of varying flow rate ratio and Reynolds number on the momentum diffusion and flow development of two co-flowing, laminar streams in a rectangular microchannel are presented. The microchannel has an aspect ratio of approximately 16 with a width of 1006 μm and a height of 63 μm. A...
Impact point dispersion of a direct fire rocket can be drastically reduced with a ring of appropriately sized lateral pulse jets coupled to a trajectory tracking flight control system. The system is shown to work well against uncertainty in the form of initial off-axis angular velocity perturbations as well as...
The goals of this research were first to examine flame quenching in tubing smaller than the quench diameter, and then to place lower size limits on microcombustor and microreactor systems by studying a catalytic microcombustor burning propane. In the first set of experiments, flame quenching was examined as a function...
A first generation, one-dimensional predictive model is proposed for designing heat sinks with fractal flow networks. A three-dimensional computational fluid dynamics (CFD) model is analyzed as a means for validating the model and identifying areas for improvement. Two separate CFD models were developed. One was analyzed with conjugate heat transfer...
Pure aluminum deformed in torsion (shear) at elevated temperatures reaches
a broad "peak" stress and then undergoes about a 17% decrease in flow stress with
deformation to roughly 1-2 equivalent uniaxial strain. Beyond this strain the flow
stress is approximately constant. The sources for this softening are unclear. The
suggested...